Rosen has worked in films and television in the US, France and in the UK. She played Tamara in the Roland Emmerich film 2012.

Rosen played a role in the eighth season of the WB series Charmed as innocent Maya Holmes as Piper Halliwell's first new identity. She appeared in the fourth season of the WB series Smallville as Dawn Stiles, a girl who wanted desperately to be prom queen. She also portrayed Gabrielle la Claire, daughter of the French ambassador in the 2004 film Chasing Liberty, and Natascha, the prima ballerina and Bruce Wayne date, in Christopher NolanThe Dark Knight. She appeared in Sharpe's Peril of the Sharpe series in 2008. Rosen was a series regular on the comedy series cuts in 2005-06 and, in 2015, on the Fox drama Backstrom as Nadia Paquet.